Sajid Javid made the comment as more positive economic figures were published, showing that British exports have risen to a record level and the construction sector is growing faster then expected.

Mr Javid, the economic secretary to the Treasury, used an article on the Telegraph website to claim that the economy is on the mend, and warn that a Labour government would jeopardise the recovery.

“While there is still a long way to go, the plan is working. The economy has moved out of intensive care and into recovery,” he said. “Momentum has returned to our economy.”

The new figures on exports and construction follow data this week showing that house prices, car sales and manufacturing are all rising strongly. The Bank of England this week increased its forecasts for economic growth this year and next.

Mr Javid’s comments come as the Conservatives launch a new attack on Labour over the economy.

After more than three years of economic gloom, Tory strategists are increasingly confident about the recovery and believe that the economy can now be used as an issue against Labour.

Conservative Campaign Headquarters has produced calculations which it says Labour is committed to borrowing an extra £50 billion a year if it takes office.

Labour’s Ed Miliband has said he would accept Coalition plans to cut Whitehall departments’ budgets, but could borrow more to fund infrastructure spending.

According to the new Tory attack, Labour would borrow £2,960 for every household in Britain.

A new Conservative poster will today present that figure as the bill for electing Mr Miliband’s party, describing the opposition as “Same Old Labour”.

Some economists say that prospects for the UK economy have been boosted by Mark Carney, the new Governor of the Bank of England, who this week signalled that he will keep interest rates at their current record low for at least three more years.

That has added to talk of a new bubble in the housing market – figures already show that buy-to-let mortgage applications are rising fast.

The Bank sets interest rates independently of the Government, but ministers are keen to take credit for low rates that help hold household borrowing costs down.

Mr Javid said that Labour’s economic policy would make it harder for the Bank to hold down interest rates.

More Government borrowing would unnerve the financial markets who buy Government bonds, leading investors to demand higher interest rates on those loans, the minister said.

That would push up borrowing costs, he said.

“If we were to adopt Labour’s policy, we would send a message to the financial markets that we weren’t serious about paying our way.

“It would spark a market crisis. Mortgage rates would soar – Bank of England figures show that if they rose by just one per cent, homeowners’ debt service bills would rise by £1,000 on average. Job losses and business insolvencies would follow.”